[PATCH] index-pack: eliminate unlimited recursion in get_delta_base()
From: Nguyễn Thái Ngọc Duy <hidden>
Date: 2016-06-15 22:52:34
Subsystem:
the rest · Maintainer:
Linus Torvalds
Revert the order of delta applying so that by the time a delta is applied, its base is either non-delta or already inflated. get_delta_base() is still recursive, but because base's data is always ready, the inner get_delta_base() call never has any chance to call itself again. Signed-off-by: Nguyễn Thái Ngọc Duy <redacted> --- builtin/index-pack.c | 30 +++++++++++++++++++++--------- 1 files changed, 21 insertions(+), 9 deletions(-)
diff --git a/builtin/index-pack.c b/builtin/index-pack.c
index 0945adb..103e19c 100644
--- a/builtin/index-pack.c
+++ b/builtin/index-pack.c@@ -508,10 +508,25 @@ static void *get_base_data(struct base_data *c) { if (!c->data) { struct object_entry *obj = c->obj; + struct base_data **delta = NULL; + int delta_nr = 0, delta_alloc = 0; - if (is_delta_type(obj->type)) { - void *base = get_base_data(c->base); - void *raw = get_data_from_pack(obj); + for (; is_delta_type(c->obj->type); c = c->base) { + ALLOC_GROW(delta, delta_nr + 1, delta_alloc); + delta[delta_nr++] = c; + } + if (!delta_nr) { + c->data = get_data_from_pack(obj); + c->size = obj->size; + base_cache_used += c->size; + prune_base_data(c); + } + for (; delta_nr > 0; delta_nr--) { + void *base, *raw; + c = delta[delta_nr - 1]; + obj = c->obj; + base = get_base_data(c->base); + raw = get_data_from_pack(obj); c->data = patch_delta( base, c->base->size, raw, obj->size,
@@ -519,13 +534,10 @@ static void *get_base_data(struct base_data *c) free(raw); if (!c->data) bad_object(obj->idx.offset, "failed to apply delta"); - } else { - c->data = get_data_from_pack(obj); - c->size = obj->size; + base_cache_used += c->size; + prune_base_data(c); } - - base_cache_used += c->size; - prune_base_data(c); + free(delta); } return c->data; }
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1.7.8.36.g69ee2